/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.hadoop.hbase.client;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.yetus.audience.InterfaceAudience;

import org.apache.hbase.thirdparty.org.apache.commons.collections4.CollectionUtils;

/**
 * Performs multiple mutations atomically on a single row. The mutations are performed in the order
 * in which they were added.
 * <p>
 * We compare and equate mutations based off their row so be careful putting RowMutations into Sets
 * or using them as keys in Maps.
 */
@InterfaceAudience.Public
public class RowMutations implements Row {

  /**
   * Create a {@link RowMutations} with the specified mutations.
   * @param mutations the mutations to send
   * @throws IOException if any row in mutations is different to another
   */
  public static RowMutations of(List<? extends Mutation> mutations) throws IOException {
    if (CollectionUtils.isEmpty(mutations)) {
      throw new IllegalArgumentException("Cannot instantiate a RowMutations by empty list");
    }
    return new RowMutations(mutations.get(0).getRow(), mutations.size()).add(mutations);
  }

  private final List<Mutation> mutations;
  private final byte[] row;

  public RowMutations(byte[] row) {
    this(row, -1);
  }

  /**
   * Create an atomic mutation for the specified row.
   * @param row             row key
   * @param initialCapacity the initial capacity of the RowMutations
   */
  public RowMutations(byte[] row, int initialCapacity) {
    this.row = Bytes.copy(Mutation.checkRow(row));
    if (initialCapacity <= 0) {
      this.mutations = new ArrayList<>();
    } else {
      this.mutations = new ArrayList<>(initialCapacity);
    }
  }

  /**
   * Add a mutation
   * @param mutation The data to send.
   * @throws IOException if the row of added mutation doesn't match the original row
   */
  public RowMutations add(Mutation mutation) throws IOException {
    return add(Collections.singletonList(mutation));
  }

  /**
   * Add a list of mutations
   * @param mutations The data to send.
   * @throws IOException if the row of added mutation doesn't match the original row
   */
  public RowMutations add(List<? extends Mutation> mutations) throws IOException {
    for (Mutation mutation : mutations) {
      if (!Bytes.equals(row, mutation.getRow())) {
        throw new WrongRowIOException(
          "The row in the recently added Mutation <" + Bytes.toStringBinary(mutation.getRow())
            + "> doesn't match the original one <" + Bytes.toStringBinary(this.row) + ">");
      }
    }
    this.mutations.addAll(mutations);
    return this;
  }

  @Override
  public byte[] getRow() {
    return row;
  }

  /** Returns An unmodifiable list of the current mutations. */
  public List<Mutation> getMutations() {
    return Collections.unmodifiableList(mutations);
  }

  public int getMaxPriority() {
    int maxPriority = Integer.MIN_VALUE;
    for (Mutation mutation : mutations) {
      maxPriority = Math.max(maxPriority, mutation.getPriority());
    }
    return maxPriority;
  }
}
